An electric vehicle, such as a hybrid electric vehicle (HEV) and the like, generally utilizes one or more electric motors that may alone, or together with an internal combustion engine, propel the vehicle. The electric motors typically are three-phase alternating current (AC) motors, such as a permanent magnet motor. The AC motors are controlled by three-phase AC currents, which in turn are controlled by three-phase AC inverters within electric motor controllers. A processor or primary module is used to control the inverter, and therefore the torque output of the electric motor.
The electric vehicle may include secondary modules that monitor the state of health of the primary module. The state of health of the primary module may refer to whether the primary module is operating appropriately and/or has one or more faults. The secondary modules may perform diagnostic tests on the primary modules to determine the state of health of the primary modules. A module is determined to be healthy if it functions in a predetermined way for its intended purpose.